Powerful winds have pushed through and downstream of regional gaps in the Cascades and other regional mountain barriers.
Consider the maximum gusts observed this morning (see below).
There are three swaths of wind exceeding 40 mph (yellow colors). One extends southwest of Bellingham and heads over the San Juan islands and then westward out the Strait.
The other extends westward north of Mount Rainer and out to Tacoma. And another extends from the western Columbia Rivr Gorge and then over Portland and the northern Willamette Valley.
There are a few odd strong winds over some exposed ridges, like one near the Tri-Cities.
So what is going on here?
We start with a very large difference in pressure across the Cascades. Sea level pressure (solid lines) and near-surface temperatures (color shading, blue and purple indicated cold air) for 4 AM this morning are shown.
There is a very…